(Chinese yam; Shan yao)
Tall climbing vine with white, cinnamon-scented flowers and edible tubers that weigh up to 2kg (5lb). Traditionally used as a herbal tonic and as a contraceptive. It stimulates the stomach and the spleen and has been used to treat diabetes, asthma, diarrhea, and emotional instability. Reported to have survived zone 3 in Alberta. Propagated by small aerial-borne bulbils.